A method of manufacturing a laminated wafer is provided by forming a silicon film layer on a surface of an insulating substrate comprising the steps in the following order of: applying a surface activation treatment to both a surface of a silicon wafer or a silicon wafer to which an oxide film is layered and a surface of the insulating substrate followed by laminating in an atmosphere of temperature exceeding 50° C. and lower than 300° C., applying a heat treatment to a laminated wafer at a temperature of 200° C. to 350° C., and thinning the silicon wafer by a combination of grinding, etching and polishing to form a silicon film layer.